It is expected that “green curtain” have the cooling effect of indoor thermal environment by shutting out the sunshine in summer season. However the cooling effect of green curtain which had been gained from the research about the reduction of electricity use of households who installed green curtain was more than the cooling effect from the result of experiment which had measured the indoor thermal environment. Therefore, on the assumption that green curtain influence the psychological reaction of indoor feeling temperature, the experiment, participants stated feeling temperature in the rooms which setting up green curtain or not, was conducted at the apartment building owned by Urban Renaissance Agency. At the result, when sensible temperature: SET∗ of rooms are equal, the stated temperature of participants in room which setting up green curtain was low than the stated temperature in the room of no green curtain. We could recognize that green curtain influenced the psychological reaction of participants.

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Trachelospermum asiaticum, T. jasminoides var. pubescensand T. jasminoides var. jasminoides are commercially distributed in Japan. In this study, we analyzed these three lineages by RAPD in order to acquire taxon-specific RAPD markers. We found RAPD markers which could be used for identification of three lineages. Using these markers, Trachelospermum plants for landscape collected from nurseries were analyzed and identified. Variegated cultivars were also analyzed and the results suggested their origins. RAPD analysis indicated that non-native T. jasminoides var. pubescens is also commercially distributed in Japan. Furthermore, progenies of cultivated Trachelospermum plants were analyzed by RAPD. The taxon-specific markers indicated the possibility that natural hybridization between T. asiaticum and T. jasminoides var. pubescens, and between native and non-native T. jasminoides var. pubescens occurred.

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The species diversity and population of dragonfly larvae are spatially different. In this study, we did mesocosm experiments to examine the effect of litter supply on the dragonfly larvae community. Size and species composition of dragonfly larvae and presence / absence of chironomid, a food resource for dragonfly larvae, were also controlled in the experiment. The results indicated that the litter provide the hiding places for small larvae, and consequently extend the survival time of them. Therefore, the litter supply regulates the structure of the dragonfly larva community.

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We profiled leaf cations and osmolytes in Bruguiera gymnorrhiza, Rhizophora stylosa, Sonneratia alba, and Avicennia marina growing on Iriomote Island in order to compare those concentrations (1) among four mangrove species growing in the estuary of the Shiira River, (2) between day and night in four species, and (3) among locations along the Shiira and Maira Rivers in B. gymnorrhiza and R. stylosa. No significant correlation was detected between concentrations of osmolytes and leaf Na⁺:K⁺ at the estuary of the Shiira River. Comparisons between day and night indicated that total sugar concentration in the daytime was higher than at night in R. stylosa and A. marina. Significant correlations were found between leaf osmolytes and salinity, pH, and deissolved oxygen in river water in B. gymnorrhiza. These results indicate that osmotic adjustment does not change within the distributional range of each species.

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To estimate the effects of rainfall and spatiotemporal fluctuation of artificial forest stand age on probability of shallow landslide occurrence, distributed shallow landslide model that incorporated the effect of stand age on soil strength parameter was applied to artificial forest of Hinoki Cypress stand (area: 3.1km²) of Utsunomiya University forest at Funyu during 33 years between 1979 and 2011. In this area, the heavy rainfall in late of August 1998 caused shallow landslides mainly in the 20 years stand age area. After consecutive rainfall data during 33 yeas were divided into 2303 individual rainfall events bounded by periods (>24 h) of no rainfall, 33 heavy rainfall events ranked in the top 33 of event rainfall amount were chosen as model input rainfall events. As the calculation start condition of this model, antecedent rainfall index induced from probabilistic analysis of 33 heavy rainfall events is applied, because of this model is calculated under the wet condition. Although the spatial landslide prediction rate is not high, the calculation results shows that the highest probability of shallow landslide occurrence is late of August 1998, and the highest probability of shallow landslide occurrence in spatial stand age distribution is that of 1981.

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Riverbank construction is usually accompanied by revegetation of bare soil using block sodding of a single species. With the aim of developing a technique for introducing several species simultaneously, we performed a 1-year experiment to clarify the initial effect of block sodding of turf in two soil types and different sowing densities on the restoration of species representing semi-natural grasslands. Cirsium oligophyllum (Franch. et Sav.) Matsum., Adenophora triphylla (Thunb.) A. DC. var. japonica (Regel) H. Hara, Aster iinumae Kitam. ex Hara, and Salvia japonica Thunb. were sown in the joints of turf in experimental trays. Germination rates differed markedly among species. Significant positive effects of block sodding were observed in terms of the germination rate of C. oligophyllum and A. iinumae individuals at the seedling stage, whereas subsequent competition with turf increased the risk of mortality of established individuals. Soil from arable fields resulted in lower survival rates of C. oligophyllum and A. iinumae than that collected from riverbanks. Survival rate of C. oligophyllum was negatively significantly associated with sowing densities.

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The fabaceous shrub Caragana korshinskii Kom. is native to northern China and is commonly used for dune revegetation. However, the sustainability of revegetation by C. korshinskii depends on natural regeneration through seeds. We surveyed seed dispersal and seedling dynamics of C. korshinskii on a revegetated dune in Inner Mongolia, China and evaluated the possibility of natural regeneration. Seedling emergence and death were affected by changes in soil moisture caused by rainfall. The number of seedling that emerged during the study period corresponded to 6 % of the seeds dispersed, and about half of the seedlings survived till autumn. Natural regeneration was possible in C. korshinskii on a revegetated dune in Inner Mongolia, but it may be affected by the rainfall pattern during the summer. As livestock was excluded in this study, grazing effects should be considered in the future research.

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Growth, photosynthesis, cation distribution and betaine accumulation in current year-old cuttings of Salix psammophila C.Wang et Ch.Y.Yang and S. matsudana Koidz. cultured hydroponically in 2/5 Hoagland solution containing 0，50，or 100 mM NaCl were investigated. The treatment of 100mM NaCl greatly suppressed growth and photosynthesis of both species. In both 50 and 100mM NaCl treatments, Na⁺ accumulation occurred in roots of both species. The accumulation of Na⁺ in leaves of 100mM NaCl treated S. matsudana cuttings was greater than that of S. psammophila cuttings. In leaves of both species, 100mM NaCl slightly increased glycine betaine content and 50mM NaCl enhanced β-alanine betaine increment. Effects of methyl jasmonate (MeJA) solution (0, 1, 5 or 10mM) sprayed to leaves on growth and physiology of the cultured cuttings also were studied. The application of MeJA solutions did not affect growth, physiology or bataine accumulation in both species.

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Several experiments were carried out to investigate morphology and germination trait of achene in Rumex nipponicus, endangered species, for understanding basic characteristics of this species for its conservation. In our experiments on the germination trait, stratification (low and/or high temperature) and dry-dark treatment were performed; R. nipponicus achene consists of three pieces of perianth with long spines in their edge like R. obtusifolius. However, the former possesses a protuberance in each perianth unlike the latter, which has just one in total. On the other hand, achene of R. nipponicus would not be likely to have deep dormancy because, for instance, the effects of stratification and dry-dark treatment on their germination were not indicated.

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In order to use for revegetation, we investigated the composition of soil seed bank both in 2005 and 2012. We collected 255 soil samples (20 cm × 20 cm × 5 cm in depth) from three districts in Hyogo prefecture, Japan. We counted emergent seedlings in the soil samples placed in an open space, and estimated the composition of soil seed bank. The environmental factors affecting the seed density and the number of taxa were analyzed using a generalized linear mixed model. The sampling year and the slope type were selected as variables for predicting the seed density. The seed density in 2005 was more on the valley slope> the straight slope> the ridge slope, but the seed density in 2012 was lower regardless of slope types. The composition of soil seed bank in 2012 against 2005 has significantly reduced in the ruderal species and the grassland species, but has almost unchanged in the coppice / summergreen species or the evergreen species. Changes of soil seed bank indicate that reestablishment of revegetation goal is necessary, assessment of soil seed bank potential is essential, and that control of surface erosion is required.

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Using surveys targeting users of rooftop green spaces on commercial buildings in city centers, we analyzed user activities and feelings about rooftop green spaces effects. Results show benefits of rooftop green spaces in everyday life and the relation between their effects and user activities. Results indicate that, as expected, 80% of users experienced stress reduction and other positive effects of the scenery, and that the versatility of strolling-centered activities has various effects. Harnessing the location and attractiveness of commercial buildings in city centers, rooftop green spaces can contribute toward improving quality of life for various city dwellers.

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Populus simonii is one of the effective species for revegetation of arid lands in China, because of rapid growth, adventitious root formation and high resistance to being buried in sand. To evaluate the effect of sand burial on water use and growth of Simon poplar, we compared physiological characteristics of Simon poplar on a slope of a sand hill (sand burial site) and on flat plane at the base of the hill (reference site) in growing season of 2012. Although sap flux density and its response to water vapor deficit were similar between the sites, leaf scale measurement of stomatal conductance and transpiration were lower in the sand burial site than the flat site. Whole-tree sap flow was larger in the sand burial site due to larger tree size.

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We analyzed the action to the plants and plants which are composed by the main anthologies of Japanese poetry compiled in order to examine the Culture of revegetation during ancient to medieval times with few data. As a result liking of the composed plant was changing from bush clover to the cherry tree from the Nara period to the Heian period. And act about planting and vegetation management occurred as an act in connection with revegetation. Moreover, hown that the various relation by a plant existed in the Nara period. However, it was shown by the time after it that consciousness faded to the act of planting.

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The vegetation cover rate of a greening-type block revetment in a steep installation depends on the block shape. We evaluated the greening performance of several greening type block revetments set up in the same river during 8 years. The block revetments are classifiable as gap type, pot type, or box type, with average opening areas of 0.06，0.07，and 0.25 m²/m², respectively, and average respective planted base soil volumes of 0.29，0.13，and 0.33 m³/m² each. The pot type average vegetation cover ratio was low: 24 %. In September, plants grew sufficiently except the pot type is unsuitable for greening. The box type with a large opening had a high vegetation cover rate as 70 %, with arbors invading into each box type division. Therefore, the box type accommodated the invasion of arbors. River management taking advantage of arbors was expected. The gap type showed a difference in the vegetation rate in the adjoining division: 41 % on average. Regarding the herbs, alien species accounted for most. The need for measures to push forward greening because of the native species was suggested.

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Vegetation structures between north- and south-facing slopes were studied on 38 points near Yan'an, Loess Plateau. In each point, slopes were divided into 5 vegetation types based on the analysis of landscape images. In north-facing slopes, broad-leaved trees occupied larger area than that in south-facing slopes. Bare ground was larger on the south-facing slopes, especially at arid site. The effects of slope aspect and topography were clearer at relatively moist site than relatively arid site. The slope aspect and topography were the regulated factors of forest development at semi-arid regions. It may be useful to evaluate the place that is difficult to tree-planting based on the existing revegetation technique.

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Control test of radioactive transport was done from June to November in 2012 on the cut slope at the edge of deciduous broadleaf hill forest in Yamakiya District of Kawamata Town, Fukushima Prefecture. After removing vegetation and litter, 6 decontamination and erosion control treatment plots were set. Though radioactive substance as decreased in the treatment plots at first, it became stopped later due to the development of vegetation. The downward movement of 1.5-8.6 kBq/m² of radiocesium was observed in the test plots during 4 and half months. Almost radioactive substance moved downwards as the form of sediment and litter. It was effectively controlled by the combination of fence and permeable mat.

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Budburst phenology of tree can be valid for tree condition assessment in general. However, this has been little verified by covering many individual trees. In this research, we clarified the relationship between flower and leaf budburst phenology of 102 individuals of Cerasus jamasakura in 4 plots and its visual tree vitality index in Yoshinoyama, Nara prefecture, Japan. The results showed that greater standard deviation within a population regarding budburst phenological date such as leaf bud opening, flower bud opening, leafing out, flowering, leaf developing and full flowering tends to be related to lower tree vitality compared between the populations which was planted at mostly same time. Further research is necessary to compare budburst phenology and quantitative vitality data and to develop objective method to identify budburst phenology for health assessment of tree populations.

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The optimum management of re-vegetation fields, non-destructive testing method for evaluation of environmental stress of plant is now in urgent demand. In this study, characteristics evaluation of frequency of detected acoustic emission waves generated from plants is going to be performed, applying bubble motion model. In water stressed conditions, elastic waves are emitted from gas-liquid flow in plant vessel. The characteristic of frequency of detected elastic waves by AE is similar to the analytical results by using the Rayleigh-Plesset equation. Thus, the water stress condition in plant is quantitatively evaluated by AE.

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The visiting frequency of flower-visiting insects was surveyed by interval timer shooting, and a pollination experiment,including inflorescence bagging and artificial pollination, was conducted to clarify the role of flower-visiting insects on the fruiting of black locust, which is a dominant tree species on the floodplain along the Tama River. As a result of interval shooting, 90% of flower-visiting insects were western honeybees. Interval timer shooting enabled to estimate insects visiting times, because the number of photos of honeybees obtained by interval shooting and the video-recorded time of honeybees were positively correlated with a high coefficient of determination. Bagging inflorescences and self-pollination resulted in a very low fruiting rate, indicating that black locust exhibits self-incompatibility. However, a significant correlation between honeybees visiting frequency and fruiting rate could not be demonstrated. Therefore, the low fruiting rate of black locust is assumed to be determined by a factor other than the visiting frequency of insects.

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